.

Females:

•  cuticular annuli often wide anterior to vulva, then flattening out to disappear posterior to esophageal region.
• Mouth opening circular or triangular; 8 papillae or labiopapillae;
• Pair of small lateral amphids.
• Eesophagus tripartite, anterior corpus with more or less swollen base separated from posterior valvular bulb by less distinct isthmus.
• Nerve ring around esophageal corpus.
•  Intestine expanded anteriorly; glands betweeni ntestine and rectum sometimes distinct.
• Vulva anterior to base of oesophagus. Monodelphic or didelphic.
•  Ovijector sometimes present. Eggs oval or ellipsoidal, colorless or yellowish, often with a polar or lateral cuticular crest or boss, or with a lateral groove.
• Excretory pore anterior to vulva.
• Tail short, conical, or acutely pointed, or short cone with long filiform projection

Males:

•  much smaller than females.
• Excretory pore at or posterior to base of esophagus.
• Monorchic, testis reflexed or outstretched.
• Tail variableshape but never simply filiform
•  2-4 pairsof genital papillae
• Single spicule.

Ref; Zervos, 1987